That is excellent - it’s a cute advert (and pretty effective), and the elephant really looks like it’s having fun bouncing around.
Yes, they give us a cutting that already specifies the length of each shot, we can make suggestions up to about halfway during the production, but usually small changes. I’ve had lengthy negotiations with clients to add or subtract 3 or 4 frames from a shot; keep in mind that 3 or 4 frames represent about 1/10th of a second during playback.
Well, obviating the fact that a real elephant couldn’t do that, if it could getting the jumping motion to match a real world scenario is straightforward. After all, gravity acts on all objects in the same way, the downward acceleration is 9.8 m/s squared. In fact for some shots I made a big bouncing ball following the correct up and down motion of an object being shot straight up and then free falling, but then I had to fiddle with the physically correct scenario so that the elephant would hover just a little bit longer, or reach a bit higher or bounce up without stretching the trampoline all the way down to the ground. I always try to keep things as physically correct as possible, but I also know that in the end what I’m doing is art (commercialized as it may be) so I often have to bend and break a few rules to get the correct look and feel that the shot requires.